UberEATS, the online food delivery service arm of US car-sharing company Uber, started its delivery service in Seoul in a cautious manner to punch through tough competition in South Korea's saturated market backed by about 200,000 delivery workers.

Uber promised to deliver food from Seoul's best restaurants to customers in the maximum time of 35 minutes. The service was limited to Seoul's two busy areas, Gangnam and Itaewon, dotted with many unique and popular restaurants, but Uber promised to serve as an app leader in publicizing Korean food.

UberEATS, launched in Los Angeles in 2014, is available in more than 100 cities around the world. As a successful food delivery business model, it works as a bridge connecting customers and popular restaurants which are normally fully-booked, allowing UberEATS users to enjoy quality food at anywhere and at any time.

However, it remains to be seen how UberEATS can compete with domestic rivals in the country's highly competitive food delivery app market valued at 12 trillion won (10.5 billion US dollars). Data from Statistics Korea, a government body, showed that as of 2014, at least 650,000 restaurants including fried chicken franchises and pizzerias offer delivery services -- about one delivery restaurant per every 80 Koreans.

While many restaurants operate their own delivery workers, major online delivery services like Baedal Minjok, Yogiyo and Baedaltong link their businesses with small and mid-sized delivery agencies to offer services similar to UberEATS'.

The users of homegrown online delivery apps can order meals from special non-delivery restaurants as well as lunchboxes, salads and side dishes from local restaurants.

For now, UberEATS will provide its service from 11 a.m. to 10 p.m. in partnership with over 200 restaurants. It promised to gradually expand its service. Anyone can sign up to become a delivery partner with UberEATS, using the transportation of their choice, such as bicycles and motorcycles.